<!doctype html> 
<html> 
<head> 
    <meta charset="utf-8"> 
    <title></title> 
</head>
<body>
<script type="text/javascript">



var json = {};
json.a = function(){
	this.b = this
};
json.a();
console.log(json);

//{
	//a:function(){this.b = this}
	//b:{
	//	a:function(){this.b = this}
	//}
//}
/*
alert(json.length); //报错
json.a();
alert(json.length); //10
*/

</script>
</body>
</html>